Digital volume tomography is often used as an imaging radiologic tomography method in dental and otorhinolaryngologic applications. In digital volume tomography, a cone-shaped X-ray beam is directed onto a two-dimensional detector arranged at a constant distance opposite the same. The arrangement, consisting of the X-ray source and the detector, is moved around the patient's head during a scan, each scan taking 10-30 seconds.
Compared to other three-dimensional imaging radiologic methods, digital volume tomography has the advantage of a relatively low radiation exposure of a patient. However, the quality of the three-dimensional images of a patient's head thus obtained and calculated varies considerably and is hard to assess. The reasons for the varying image quality are, on the one hand, principle-related and of physical nature and, on the other hand, are due to the long scan time which makes it impossible to exclude undesirable self-motions of a patient's head, the X-ray source and the detector during a scan. Self-motions have a considerable negative effect on the image quality. In practice, the size ratios and proportions in the three-dimensional image are often represented with an error margin of up to several millimeters. Although this is not always problematic in diagnostics, digital volume tomography is, however, also used in dentistry to plan dental implants in a patient's jaw. This requires a high geometric accuracy so as to provide a high quality of the implant treatment.